Research Projects

The efficient manipulation and conversion of absorbed photons into free carriers is crucial for high-performance opto-electronic devices. Semiconducting Transition Metal Dichalcogenides (TMDs) are two-dimensional materials with unique capabilities to create van der Waals (vdW) heterostructures, which have gained attention in solar energy conversion and advanced biosensing. These materials have high carrier mobility, band-gaps, high surface-to-volume ratio, and controllable density of reactive sites. However, their low photon absorption due to their inherent thinness hinders their use in photon harvesting (PH) applications. To improve photon-absorption in 2D-TMDs, a challenging but promising approach is based on the coupling of metallic nanostructures (NSs). The collective oscillation of conduction electrons in noble metal NSs, called Localized surface plasmon (LSP) resonance, has strong ability to concentrate light within subwavelength regions. This makes it a core element for PH applications, including fast and sensitive detection of single molecules for various analytes. The proposed research project aims to synthesize innovative vdW heterostructures based on binary and ternary TMDs, tuning their optical and electronic properties using doping approaches and strain fields, and integrating them with plasmonic nanostructures for photon-harvesting and ultrasensitive near-infrared molecular sensing. High-quality 2D-TMDs of controlled thickness will be achieved via direct growth or transfer processes. Optical and electrical characterization of the hybrid plasmonic/2D system will be investigated using Raman and photoluminescence spectroscopy and l-V measurements. Ultrasensitive Surface Enhanced Raman Scattering (SERS) spectroscopy will be employed for fast and sensitive detection of trace molecules. Experimental results will be compared with simulation.